Manufacture of paper or like bag tubes or bags



Jan. 25, 1938. J JONES 2,106,431

MANUFACTURE OF PAPER 0R LIKE BAG TUBES OR BAGS Filed Aug. 15, 1934 2 Sheets-Sheet 1 f my. ,9. 7 f

p i fjigi F 113 Q 13 "15:9 a

Jan. 25, 1938. A. J. JONES 2,106,431

MANUFACTURE OF PAPER 0R LIKE BAG TUBES 0R BAGS Filed Au 15, 1954 Sheets-Sheet 2 H. 5?, Jone NVEN TOR Patented Jan. 25 1938 .MANUFACTURE OF PAPER 01!. LIKE BAG TUBES R BAGS Alfred James Jones, Bristol, England, assignor to E. S. & A. Robinson, Limited, Bristol, England Application August 15, 1934, Serial No. 740,015 In Great Britain August 22, 1933 18 Claims.

This invention relates to methods of and means for the manufacture of paper or like bag tubes or bags and an .aim of the invention is to manufacture bag tubes or bags using the continuous tubin'g principle and to provide bag tubes or bags which have a smooth-edged closure flap or overlap at the mouth, the invention being particularly intended for use with delicate or membranous material. One of the more common ways of making bags according to the continuous tubing principle, involves the folding around a former of an endless web into a continuous tube which is cut into bag lengths by a beater operatin against serrated edges. This mode of forming bags has many advantages certain of which are particularly suited to the handling of very thin paper or delicate membranous material such as that known by the registered trade-mark Cellophane. Material like Cellophane which-lacks g the stiffness and other characteristics of paper and which readily tears under certain conditions, is dimcult to handle in sheets. Hence,

the continuous tube method offers facilities for g the manipulation, handling and control of thin paper or Cellophane but the usual serrated cut affords opportunity or leads for tearing or the start of a rupture. When beater means are used, it is possible not only to sever the tube but to sever it in such a way as to leave an overlap at the mouth of the bag or an integral closure fiap. If cooperating rotary severing devices are employed it will be appreciated that normally the line of severance on one side of the tube will register with that on the other and no overlap or closure flap can be produced.

Although proposals have been made to cut bag lengths on bag tubing machines with smooth edges (as opposed to serrated edges) and at the same time to form or produce a closure flap 'for subsequently closing or sealing the open mouth over the contained goods, such have met .with little success.

The object of the present invention .is to utilize and adapt the known continuous tube forming operation for the-production of bag tubes (or bags) with smooth-edged mouths or closures (such as produced by cooperating shear edges.- including flaps or overlaps) and particularly to enable such bags or bag tubes to be manufactured successfully from Cellophane, or like transparent membranous material.

The invention broadly consists in forming bag tube lengths from a continuous tube with smooth edge cuts such that the cut edges in the finished bag are transposed and lie substantially out of register on opposite sides of the bag suchthat a closure flap or overlap is afforded and such that the mouth of the bag offers the minimum of leads or opportunity for tearing in the manipulation of thebag. 5

The invention comprises continuously forming a tube from a web, making a compound smoothedged severance (i. e. a severance cut which extends both transversely and longitudinally of the tube), opening or expanding the tube andflatten- 10 ing it in a plane substantially at right-angles, to the plane of the tube formation or the plane previously occupied, thereby transposing the posltion of the cut edges to provide a closure flap or overlap at the mouth. It is to be understood 15 that a cut of slit form as used in the appended claims means a out which permits the adjacent tube lengths to be separated without a waste or discarded portion.

The invention also comprises the features here- '2 inafter described and defined in the claims including the improved bag.

In the accompanying drawlngs:-

Fig. 1 is a perspective view showing the treatment of the paper or material according to one 25 mode irrespective of the means employed to carry out the various operations.

Fig. 2 shows a type of cut or severance line extending transversely and longitudinally of the tube.-

Fig. 3 shows thetop fragment of a bag with a closure flap such as produced by a severance line as in Fig. 2.

Fig. 4 shows the tall or bottom fragment corresponding with Fig. 3 illustrating the folding over of the tail of the bag onto the body'part in the common ways Fig. 5 shows the top fragment of a bag'produced by a modified form of severance line, producing in this case a simple overlap of the back of the bag and a curved opening lip.

Fig. 6 is a diagrammatic elevation showing the mechanism for folding the web into a tube; folding the tube at right-angles and severing. refolding the web at right-angles and finally closing the bottom of 'thebag tube lengths to form bags.

Fig. 7 is a diagrammatic elevation taken at right-angles to that shown in Fig. '2 but with the bottom forming mechanism removed as it is of known kind and in side view would afford no further information.

Fig. 8 is a perspective view of the first and second right-angle former plates or member and the severing device. The supporting frame or frames and bearings and driving means for the various rollers and severing means, as well as known auxiliary tube folding devices are omitted from the drawings for sake of clearness and-in order to avoid obscuring essential parts.

Fig. 9 is a'detail diagrammatic plan view of the rollers carried by the floating former plate and the driving and supporting rollers engaging therewith through the material of the tube.

The tube formation may be carried out in the usual way from a web by pasting or glueing one margin and folding the web around a former plate without crushing the edges. With a view to aiding subsequent operations, the web may be initially given a pair of longitudinal creases or folds one lying centrally of the body of the tube when formed and the other positioned on one margin or fold so that it lies near the seam. The

position of the creases will depend on whether the final bag tube is to have a central or side seam.

The continuousbag tube is,severed into bag lengths each severance being effected by a cut on a curved or angular line which extends transversely and longitudinally of the tube. The severed bag tubes are opened and flattened in a plane at right-angles to the plane of tube formation and severance, the initially made creases or folds giving the tube a predisposition to set in the opposite plane.

According to the preferred mode of treatment the initial creasing may be efiected in the production of the tube by forming the bag tube (pressing the folded edge between pressure rollers in the known way) in the same plane as that of the finished bag. In this case the tube is opened and flattened in a plane at right-angles to the plane of its formation and then severed, while after se'verance the tube is again opened and reflattened in a plane at right-angles to that occupied during severance.

In order that the nature of the invention may be more clearly understood, the mode last referred to will be explained with reference to Fig. l of the accompanying drawings. In Fig. 1 the web, tube and bag are-represented as passing from right to left and as viewed by a party looking slightly downward.

In stage I the web a margins are being folded inwardly in overlapping relation to form a seam b one margin having previously received a line of adhesive. The edge folds -c are pressed to give the material a permanent set. Proceeding from stage I which shows the transposition of the fold ing, the formed tube is opened, that is to say, the front and back of the tube are'separated in stage II and the tube folded as at din a plane at rightangles to the plane in which it was formed. In this stage the edges should not be crushed or given a permanent set since ultimately these margins will lie towards the middle of the bag while the initial folds c (which at this stage lie at the dotted position 0) will be restored tothe middle of the bag. As the tube leaves stage II it is severed in stage III on a curved or angularline as at e simultaneouslyforming the head 'or top of one bag tube with a flap portion 1 and the tail of the next bag tube, the severed tubes proceeding with their tail or bottom engs leading. A complete tube length is seen between'stages HI and IV.

After severing the position of the folds are again transposed, the tube being opened and refolded as shown in stage IV so that the tube is reflattened at g in a plane at right-angles to the plane of severance. In this way the tube is restored to the sense or way in which it was originally folded in stage I and, due to such initial creasing-has a predisposition to recover its origiof the bag as at h as in stage V where it will be seen that the flap part I is in its proper place for constituting a closure of the bag mouth. Alternatively, the bag tube bottom may be subjected to a block or square bottoming operation.

It it be desired to form gusseted or satchel bags gussets are folded into the web or in forming the tube in stage I but will disappear in stages II and III, being restored in stage IV.

The bagtubes may be severed on any predetermined line angular or curved to afford a flap or a mere overlap. If a curve such as seen in Fig. 2 be produced by the severing device a bag mouth as shown (in fragment) in Fig. 3 will be produced where the flap I corresponds with the severance portion I while the lip. f corresponds with the part f of the curve in Fig. 2. The bottom of the bag shown in Fig. 3 is seen in Fig. 4 where the turned up edge corresponds with the'cut at f in Fig. 2 while the dotted part I is the counterpart of I and f (Figs. 2 and 3). By modifying the curve shown in Fig. 2 and in effect reversing it, a bag mouth will be produced with the back of the bag at l overlapping a curved lip I (Fig. 5).

It will be appreciated that the operations shown in the stages illustrated in Fig. 1 may be carried out by hand with or without the aid of formers or other auxiliary appliances but-to cope with commercial output an improved bag tubing machine is according to features of the invention adapted to carry out mechanically the sequence of operations. j

According to one form it is preferred to run the web and bag tube downwardly as described here-' inafter with reference to Figs. 6 and 7 of the drawings. A web I is run off a reel 2 over a guide roller 3 to an adhesive applying device I of known kind for pasting one margin oi the web; The

web passes over a guide roller .5 to a former plate supported by the usual foot or bracket 6. The part I of the former plate is of known form and efiects the tube fold as seen instage I of Fig. 1. The lower part of the former is of special con struction adapted to open andflatten the tube at right-angles (see stage II).

Looking at Fig. 8 it will be seen that the lower part of the formerhas a plate 8 which lies at 1 right-angles to the upper portion 1 and which is joined thereto by an intermediate section 8 merging into the plate I on one side and the plate portion 8 on the other. The intermediate section comprises a double wedge form as shown.

Pressure rolls l0 nip the side folds and pass the folded web or tube forward over the plate I from whence it is drawn over the section 9 by draw rolls ll operating throughslots in the plate part 8. blunt so as not to impress a fold or crease in the material at this stage. The tube is presented to a rotary severing device I! having a blade in which is curved or angled to aiford a cut of the predetermined configuration and cooperates with a corresponding fixed blade I215. The leading end of the tube projected between the knives is supported upon the upper end of a second former or reversing plate member II the nose I311 The side edges to are rounded or of which enters the tube. The entry of the nose is made easy by reason of the fact that the of the member I3. Slots lid and I3e are provid- I ed for the location of an upper and a lower series of rollers. The upper series of rollers is illustrated in the sectional plan and numbered 13f and I3g in Fig. 9 where the former plate is seen at I3 and the upper slot at I311. The chain dotted line represents the bag tube. The outer rollers I3f cooperate with positioning rollers I5 through the material of the tube while the rollers I6 coact with the inner rollers I39. The lower slot I3e has a similar set of rollers to those shown Nil in Fig. 9 but are oppositely engaged to those of the upper set, viz. the lower locating rollers I5a engage the inner rollers of the slot I3e and the rollers IGa engage the outer set. In addition to the'rollers just described the former I3 has a pair of lateral rollers II resting upon outside rollers l8 as these are located below the rollers I1 and aiford a rolling contact and floating support for the member I3. The spindles of the rollers I5, I6, I541, Iia and I, are supported in bearings carried by the framework of the machine and all the rollers may be driven to draw the tubes downward-' ly over the former or only certain of these rollers, for example rollers I8, may be driven. It will be seen that the rollers position the former member l3 on both sides and at the same time support it within the tube. The lower end of the member I3 is provided with a slot I3h through which both sides of the tube are engaged by draw rolls IS on each side of which auxiliary rolls 20 are adapted to engage the tube on the plate I30. As the tube lengths pass over the former I3 they are again transposed and refolded at right-angles as in stage IV '(Fig. 1) and are ready for forwardin to a bottom forming device. Running tapes 2| forward the tubes as they come off the end of the plate I3c and present them to the bottom form? ing device 22. The tapes run at a speed adapted to accelerate the tubes so that they are presented in spaced relatidn to the bottom forming device.

, In Fig. 2 a known type of rotary bottom forming device 22 is diagrammatically shown where 23 represents an eccentrically operating pasting bar which picks paste from a roller 24 (operating in a paste bath 25) and applies it to the tube close to its end. Adjacent to the paste bar a dipper blade is located which creases the tail ofthe bag (actually the leading margin as it 'comes from the tapes 2i) and folds it into a gripper 26 in the opposite roller 21 of the device. As the roller I'I continues its rotation the gripper releases the -formed bag (such as seen at stage V, Fig.1) and delivers it to any appropriate collecting device or conveyor.

When it is desired to make gussetedor satchel bags, gussets may be impressed'in the material by placing gusset-forming means of known kind in extension of the former plate I. pass over the former member 9 the gussets are pushed out but the effect of their folds or creases remains so that subsequently they can bereadily As the tubes restored. In this case the rollers' II are positioned so as not to bear upon the outward fold (that is to say, whatwas the inner fold when the 5 tube was in the gusset form) so as not to impose a reverse fold. The restoration of the gusset folds is effected as the tube lengths pass on to the part I30 of the former I3. For this purpose the edges of the plate I3c are provided with gusset grooves and the usual fingers or guides are employed.

Where in this specification the term rightangling is used, it is to be understood that'the angle is not strictly limited to 90 butmay vary 'claim as new and desire to secure by -Letters Patents is:-

1. A method of forming bags or bag tubes of the character specified consisting in forming a tube from a web, transposing the sides of the tuba-severing the tube with a compound cut into bag tube lengths and transposing the position of the cut edges so that the edges of the mouth of the tubes or finished bags lie substantially out of register and provide a closure flap or overlap.

2. A method of forming bags of the. character specified consisting in forming a tube from a web, opening or expanding the tube and flattening it in a plane transverse to the plane of formation. severing the tube into bag tube lengths by a compound cut and closing the ends of the tubes to form the bottoms of the bags.

3. A method of forming bag tubes of the character specified consisting in forming a tube from a web, opening or expanding the tube and flattening it in a plane transverse to the plane of forcompound cut.

4. A method of forming bags or bag tubes of the character specified consisting in forming a tube from a web, opening or expanding thetube and flattening it in a plane substantially at rightanglesib the plane of formation of the tube, severing the tube into bag tube lengths by a -com.

pound cut, and reopening or expanding the tubesing it in a plane at right-angles to' the plane of formation; severing the tube into lengths by a compound cut and feeding the bag tube lengths in spaced relation for forming a bottom closure therein.

'mation and severing the tube into lengths by a' 6. Apparatus for making bags or bag tubes of the character specified comprising continuous tuberormin'g mechanism, former means for transposing the sides of the: tube; knife means for severing bag lengths on a compound line of severance, and means for flattenl the tube in a plane transverse to the plane of the tube previously occupied.

7. Apparatus for making bags or bag tubes of tube forming mechanism, means for forming creases in the web or tube defining the plane of formation, means for transposing the sides of the tube so that it lies in a plane other than the plane of formation, severing 'means for severing bag lengths on a compound line of severance,.and means adapted to expand the tubes and flatten them in a plane defined by the previously formed creases.

8. Apparatus for making bags or bag tubes of the character specified comprising continuous .tube forming mechanism, means for opening and flattening the tube in a plane substantially at right-angles to the plane of formation of' the tube, a smooth knife for severing the tube into bag tube lengths and means for reopening the tubes and refiattening them at right-angles 'to the plane wherein the tube was out.

9. Apparatus for making bags-or bag tubes of the character specified comprising tube forming mechanism, means for transposing the sides of the tube into a plane other than the plane of formation, a smooth knife {answering the tube into bag lengths on a compound severance line, means adapted to transpose the cut edges and means for closing the ends of the tubes to form bottoms of bags.

10. Apparatus for making bags or bag tubes of q the character specified comprising tube forming mechanism; means for transposing the folds of the tube through substantially a rightangle, a a,

smooth knife for severing the tube into bag lengths, means for transposing the cut edges through substantially a right-angle and means for closing the ends of the tubes to form bottoms of bags.

11. Apparatus for making bags or bag tubes of the character specified comprising tube forming means, means for making a compound cut in the tube at bag length intervals, a former of double oppositely disposed wedge shape for transposing the position of the tube folds and means for separating the bag lengths into bag tubes.

12. Apparatus for making bags or bag tubes of the character specified comprising tube forming means, means for severing the tube into bag lengths by a coinpoundcut, and former means comprising a pair of plate-like portions lying in transverse planes and an intermediate portion -of double wedge form for transposing the position of the cut edges of the bag lengths.

13. Apparatus for making bags or bag tubes of the character specified comprising former plate means, means for folding a web about said plate means to form a tube, a second former plate means lying on a plane transverse to the plane of said first pla'te means, .a double wedge shaped means forming a-transition between said first and said second plate means for transposing the tube folds and means for severing bag tube lengths by a compound .cut.

l4. Apparatusfor making bags or bag tubes of the character; specified comprising continuous tube folding means, means for separating bag tube lengths involving a compound cut and former means for transposing the edges of the folded tube said means having a nose portion, a platelike part of shallow wedge shape, a second plate part transverse to the first plate like part and an intermediate section of double wedge form.

15. Apparatus for making bags or bag tubes of the character specified comprising continuous tube forming means, means for separating bag tube lengths involving means for making a compound cut, a former of double wedge form for transposing the edges of the tube and roller means external to the tube for supporting the former in floating position within the said tube.

16. Apparatus for making bags or bag tubes of the character specified, comprising a former plate and means for continuously folding a tube thereabout, means for transposing the sides of the folded tube and means for severing bag lengths by a compound cut.

17. Apparatus for making bags or bag tubes of the character specified, comprising means for continuously folding a tube fromra web and impressing fold lines or creases in the tube, former means being arranged not to crush the edges of the flattened tube, and means for severing bag length by a compound cut.

18. A method of forming bags or bag tubes of the character specified, comprising continumeans for opening and flattening the tube in a ,plane other than the plane of formation, said 

